M. V. Belyi, V. E. Bulgakov, A. B. Zolotov, “A semi-iterative multigrid method and its implementation as a program for solving spatial boundary value problems”, Zh. Vychisl. Mat. Mat. Fiz., 27:6 (1987), 875–888; U.S.S.R. Comput. Math. Math. Phys., 27:3 (1987), 153–161
Contact us: